Question

A flask has a volume of 250 mL. It is filled with N2 gas at a temperature of 32°C and the pressure is found to be 1.56 atm. The number of moles of N2 (g) in the flask is equal to ___. (R = 0.0821 L. Atm/mol.k) Can someone explain how to do this??

Answer 1

0.0156moles

Explanations:

According to the ideal gas equation:

`PV=nRT`

where;

• P is the ,pressure ,of the gas (in atm)

,

• V is the ,volume ,of the gas (in L)

,

• n is the number of moles

,

• R is the ,Gas constant

,

• T is the temperature (in K)

Given the following parameters

P = 1.56atm

V = 250mL = 0.25L

R = 0.0821 L. Atm/mol.k

T = 32 + 273 = 305K

Substitute the given parameters into the formula

`\begin{gathered} n=(PV)/(RT) \\ n=(1.56*0.25)/(0.0821*305) \\ n=(0.39)/(25.04) \\ n=0.0156moles \\ \end{gathered}`

Hence the required number of moles of N2 is 0.0156moles